It does sound like the file was downloaded successfully. It seems to be a common issue. The last post on there suggests you could try to use the amd removal tool (from my previous post) and then only try the 'Auto-Detect and Install' option for the 6600 at the top of the page here. It may be best to temporarily disable windows updates to avoid conflicts. After each uninstall of old drivers and install of new, to restart the system. Note that the driver links are for the 6600, not the 6600xt.
Or manually try to download the full driver, that is usually around 700MB, and run it from that page also (currently on ver 24.12.1). It's usually best to stay on the latest one, but optional older drivers to try that may sometimes work better on older tech are also here for the 6600.
To ensure there are no system issues, scan your system with a system file check to ensure the system has no problematic system files. For example, type cmd in the start menu, choose the command prompt, and in the black box type sfc /scannow and press enter. After a while, it will report back if there are any issues. You could optionally also try a virus scan while you are at it.
A potential fix to prevent Windows Updates from installing and overwriting your manually chosen drivers for AMD Radeon graphics (entirely optional, may need to be turned on again if you ever have issues with other hardware):
- Press Windows + S keys together to open Search.
- Type Device installation settings.
- Click on Change Device installation settings and then select the option No (your device might not work as expected).
Click on Save Changes.
